Article by G. Lafaye in

Except in Attica, where herms marked the half-way point between Athens and the various demes [hermae, p131], the Greeks never thought, before the Roman conquest, of indicating the distances along the roads by milestones and inscriptions; Strabo himself remarked how inferior their road system was to that of the Romans.3 It has sometimes been maintained, from a passage of Plutarch, that the idea of marking the great public roads by milestones originated with C. Gracchus.4 Yet Polybius says that in his time already, this useful provision had been applied to the via Domitia, recently opened between the Pyrenees and the shores of the Rhône.5 While this testimony may not perhaps be much earlier than the tribuneship of C. Gracchus,6 the latter no doubt was merely formalizing into law an older invention;7 an extant milestone8 bears the name of P. Popilius, consul in 131 B.C. (fig. 5029); it was the eighty-first on a road from Rimini to Aquileia.9 Starting with Augustus the provision was made general and care was taken to indicate regularly each distance of one mile (1481.50 m) thruout the immense network of the great roads of the empire. Thence the habit of giving distances in terms of the numbers on the milestones, and of referring to ad lapidem primum, secundum . . ., etc.10 There is no emperor in whose reign some segment of road has not been built or repaired, and the work recorded by inscriptions cut on the milestones; the most recent were set up at the end of the 4th century or in the first years of the 5th.11 We know a considerable number of them; in Italy alone more than five hundred are recorded. All have been catalogued and classified by regions in the Corpus Inscriptionum Latinarum.12 Very often found at the exact place where they were set up, they provide us with firm indications as to the route of Roman roads. The numbers and the names of cities that they bear are of great help to us in the identification of places. The inscriptions on milestones inform us as to imperial titulature, so important for chronology; they also sometimes yield to us the names of magistrates and allow us to follow the history of major public works performed under the empire.

Fig. 5029. — Milestone of the Republic.

p1898
In making their milestones the Romans used materials they found on site: limestone, marble or granite.13 The shapes are rather variable; the commonest is that of a column, as much as about 3 meters high and 2 meters in circumference, although the great majority are of smaller dimensions.14 It is always of interest to note other shapes when they occur; thus, in studying the Via Domitia between Nîmes and Narbonne, it has been noticed that the shape of the milestones varies according to their date;15 those of Augustus are perfectly cylindrical columns (fig. 5030);16 those of Tiberius are rectangular pillars (fig. 5031);17 on those of Claudius the inscription is enclosed in a frame (fig. 5032).18 A milestone of Antoninus having belonged to the road from Aps to Uzès ends at the lower end by a square base.19 These differences in shape can be used as chronological indications only within the boundaries of the region where they were observed; but, subject to that reservation, they can provide points of comparison useful for dating mutilated milestones and they should not be ignored. It is probable that at first the column was not used; this is what seems to be indicated by the milestone of Popilius (fig. 5029), a flat stone the lower end of which is roughly hewn to a point for sticking it into the ground. Gradually columns will have replaced these primitive milestones on roads of the Republican period.20 In exceptional cases, the information we usually read on milestones has been cut instead on a bare rock face next to the road.21

Fig. 5030. — Milestone of Augustus.

Fig. 5031. — Milestone of Tiberius.

Fig. 5032. — Milestone of Claudius.

Roman roads fall into two major categories: the imperial roads, also called consular or praetorian (viae consulares, praetoriae, βασιλικαί), built and maintained chiefly at the expense of the State; and secondly the viae communales and vicinales, roads built and maintained chiefly at the expense of the towns [via].22 The milestones we have may come from the latter as well as the former, since we know from the inscriptions cut on some of them, that the municipalities took care to set some up on their road systems: respublica miliaria constituit;23 but it might happen that at their request the emperor gave them a grant: in that case the milestone was erected ex auctoritate imperatoris, which in no way indicates that the road was classified among the imperial roads.24 It must not be forgotten either that Roman roads were originally built in large part for the needs of the armies; State roads are thus par excellenceviae militares,25 and it is often the legions who performed the work.26 Milestones allowed troop commanders to calculate stages with certainty and guided them in their operations.27 Narbonensis had barely been conquered when already the Romans were edging the via Domitia with milestones starting out from Narbonne;28 it can therefore be concluded that many of these monuments were the work of soldiers.

In Italy, the distances were counted from Rome. In the year 29 B.C., when Augustus, assisted by Agrippa, drew up the map of the Roman world, a zero milestone was erected in the forum, which was given the name "golden milestone" (milliarium aureum).29 It was at the end of the forum, between the Rostra and the temple of Saturn.30 A trace of it has even been found: a cylindrical marble base measuring four and a half feet in diameter; above it must have risen a column plated in gilt bronze, whence the name of the monument.31 Distances properly speaking, however, were not computed from this point, but from the gates in the Servian wall, which formed the terminus of the great Italian roads, so that the space
p1899within the capital itself was not included in the count. An inscription cut on the milestone probably indicated the main stations along each route, with across from them the number of miles separating them from the walls of Rome.32 In the provinces, on communal roads the miles were counted from the town that had paid for them to the end of its territory; on imperial roads, from the capital of the province.33

It has happened, especially from the 3rd century on, that instead of planting new milestones when a road was repaired, the old ones were pressed into service, the inscriptions in honor of the previous emperors being filled in with cement and a new inscription cut over it.34 In the East, milestone inscriptions are often bilingual; on some the text is in Latin, but next to the Latin numeral expressing the number of miles the corresponding Greek numeral was given;35 on others the entire Latin text is translated into Greek.36 Milestone inscriptions are far from being all phrased according to some standard formula; the information they contain is very variable and the tenor of it may sometimes vary along one and the same road and over a short interval of terrain: for the most part, this may be attributed to their dating to different periods. Here are the results of the observations made by epigraphers on all these documents:

1. The distance may not be given at all (fig. 5030 and 5032), or given by a number (fig. 5029, 5031), or yet again by a number preceded by the abbreviation m. p. (millia passuum). Generally this indication is given at the end; in Italy, the milestone sometimes bears two numbers, the first counted from an unnamed nearby town, the second from Rome.37 On some milestones the name of the base town is given: a Sitifi, a Caesarea,38 and on occasion the endpoint of the road is indicated: a Baete ad Oceanum.39 Rarer are milestones marking distances to several different towns.40 In the three Gauls and in the two provinces of Germany, the distance is expressed not only in miles, but in Gaulish leagues (L or leugae),41 a unit which was equivalent to a mile and a half, and thus, according to the most probable estimate, 2.222 km.42

2. Under the Republic, the inscription states the names and titles of a superior magistrate (fig. 5029); under the Empire those of the prince (fig. 5030, 5032).43 If they are in the nominative, the road is a State road; if in the dative, it is a city road; the ablative merely records a date.44 On State roads, the name of the emperor is sometimes followed by a verb: fecit, stravit, munivit, refecit (fig. 5031, 5032), etc., or even by a clause that states the nature of the work, giving the purpose and the obstacles involved; thus on a milestone of Tiberius one reads: Viam Claudiam, quam Drusus pater, Alpibus bello patefactis, derexserat, munit a flumine Pado ad flumen Danuvium.45

3. Milestones are known where after the emperor, the governor of the province in charge of the works and their supervision is named, and who inaugurated the road: Commodus restituit, curante et dedicante L. Junio Rufino Proculiano, leg(ato) pr(o) pr(aetore);46 or the legion who performed the work: Hadrianus viam stravit per leg(ionem) III Aug(ustam).47

4. On the milestones of communal roads the town in charge of them sometimes adds its name; thus in Africa: Respub(lica) gent(is) Suburbur(ensium) vias exaustas restituit ac novis munitionibus dilatavit.48

Finally one meets also with milestones that indicate the source of the funds, for example if the emperor added a grant to the amount provided by the neighboring landowners: adjectis sestertiis XIXLVII ad sestertia DLXIX C quae possessores agrorum contulerunt.49

II. — A tall narrow boiler, the cylindrical shape of which was reminiscent of that of a milestone; it was used to heat water in baths [balneum, p660, fig. 765].50

6
Polybius died around 129‑127 and the date at which he published the definitive edition of his work is debated. Several scholars have thought the passage interpolated; it is considered authentic by Mommsen and Hirschfeld, CILV, p885, XII, p666; but one could see in it the trace of a redrafting done by the author himself.

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7
The passages of Livy
II.11.7; III.6.7
and
69.8;
V.4.12;
Flor. II.6;
Justin. XXII.6.9 are mere anachronisms by these historians. But no one until now has remarked that miliarium in Cato, R. R.20,
22
and 135, necessarily supposes the use of milestones on roads before the year 149 when Cato died, and even it could not be new at that date.a

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8
The milestones of the Corp. Inscr. Lat.I.535, 536, 537 (year 186), 540 (year 147), name persons from a previous time; but their inscriptions seem to betray a more recent hand.

12
The comprehensive bibliography of each monument is also given there, which allows us to forgo listing here the specialized literature, which remains useful, however, for studying the subject in depth.

20
Some scholars have credited C. Gracchus with this reform and have thus sought to harmonize
Plut. C. Gracch. 7
and
Polyb. III.39.8. But their opinion is unlikely. The so‑called milestone of the Via Appia, adduced as an example by Rich, Dict. of antiq.s.v. and by Duruy, Hist. des Rom.I, p151, is a restoration by Canina that seems to be made up of unmatched pieces; it is not possible to study the original, preserved on the Capitoline, from up close, and its provenance is doubtful: CILX.6812, 6813.

Thayer's Note: The estimate, traditionally extracted from a single reference in Ammian, has been improved on by a very clever piece of detective work; see my note to the article
Milliare
in Smith's Dictionary of Greek and Roman Antiquities, and the further links there.

Thayer's Note:

a
A puzzle in our Dictionary: although stones are mentioned in each of these passages of Cato's Re Rustica, and they are called milliarium, the context is very clear: they are not milestones but millstones.

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